Chapter 1

Introduction to Statistics

Why do we care?

Statistics is the backbone of criminology and criminal justice.

But Even More Important!

Statistics is everywhere!!!

Statistics is everywhere!!!

Arrests Rate

One of the most common statistics used in criminology and criminal justice.


It signifies the number of people arrested within a population during a certain time frame - usually in a given year.


\[Arrest Rate = (Number of Arrest/Total Population) x Multiplier\]

Where else do you see or use statistics?

Let’s review some basic terms

is the process of gathering and analyzing data in a systematic way using procedures (i.e., methods) that are accepted across a discipline.

Sample vs. Population

  • Any guesses?


  • A Population is the universe of people, objects, or locations that researchers wish to study.


  • A Sample is a subset pulled from the population in order to make generalizations about the universe of people, objects, or locations within that population.

Pop Quiz!

Which of the following is a sample?


a.) The number of women in the University

b.) The number of prisoners within a prison

c.) All of the people in the state of Michigan.

d.) A group of 100 police officers pull from a department

Replication

Thoughts?


Why would a statistics book emphasize replication?


  • Replication is conducted for the purpose of determining if a study’s results hold when a new sample measures a previous study’s findings.

Hypothesis and Theories

Theory is a set of proposed and testable explanations about reality that are bound together by evidence.


Hypothesis a single proposition deduced from a theory, that must hold true in order for the theory itself to be considered valid.

Types of Scientific Research

Evaluation Research

  • Examines the results of program to assess whether the programs are effective

Exploratory Research

  • Examines issues that have been understudied and thus lack theoretical or empirical grounding

Descriptive Research

  • Studies done for the purpose of describing a phenomena that occurs in a population

Probability Sampling is a sampling technique in which all people, objects, or areas in a population have a known chance of being selected into a sample.

Software for Statisitical Analysis

We will touch lightly on software in this class.

Specifically, we will be using R through Posit Cloud.

But we won’t dive into that until later in the semester.


Have a great day!